The purpose of this application is to initiate a collaborative investigation between faculty at Forsyth Dental Center and NYUCD with the long term goal of determining the severity, progression and pathogenesis of periodontal diseases in defined minority populations. The study population will consist of 100 Black, 100 Hispanic and 100 Asiatic patients at NYUCD; each group divided onto 50 periodontally healthy subjects and 50 subjects exhibiting evidence of periodontitis. Subjects will be monitored at baseline and 2 months. Clinical indices recorded at 6 sites per tooth will include redness, plaque, bleeding on probing, suppuration, pocket depth, attachment level and subgingival temperature. Subgingival plaque samples from the 4 deepest sites in diseased subjects and 4 matching sites in healthy subjects will be analyzed by colony lift and DNA probe hybridization for 9 subgingival bacterial species; A. actinomycetemcomitans serotypes a and b, B. forsythus, P. gingivalis, P. intermedia homology groups I and II, C. rectus, C. ochracea, and S. oralis. Serum samples will be analyzed by ELISA for IgG antibody to a panel of periodontal pathogens. These will include A. actinomycetemcomitans, serotypes a, b, and c, B. forsythus, F. nucleatum as vincentii, P. gingivalis, P. intermedia, C. rectus, B. gracilis, C. concisus, C. sputigena and E. corrodens. The results will relate specific clinical, microbiological, immunological, and demographic variables to the risk of new attachment loss in minority populations. These results will also permit an estimate of periodontal disease severity, prevalence and progression in three urban minority groups when compared with similarly derived data for a predominantly White population under study at Forsyth. The proposed study will provide the basis to design comprehensive studies on minority populations, provide access to current methodologies in clinical research for faculty development and aid in the formulation of strategies to control periodontal diseases in minorities.